Bottom line up front: the next Democratic nominee will not be allowed to run a fake field campaign, which is what happened in 2016. This was not entirely Hillary’s fault. The fake field campaign should have actually worked and would have, if not for the Comey letter (1) and Russian interference (2).
The fake part was the way the Clinton campaign made it look, to experienced volunteers and inexperienced field staff, that the field campaign was being run similar to the two successful Obama campaigns in 2008 and 2012, but that was a fraud. What happened instead was, Hillary's top campaign advisors made a fortune off bulk TV ad buys (3). About 70% of Hillary's $ billion dollar campaign budget went for television ads (4). The rest went to social media, campaign lit, mail, staff and offices.
Hillary's campaign advisors conveniently decided that all Hillary needed to do to win, was to get Democratic voters out to vote. No persuasion. No targeted messaging and no need to clean up the voter lists for GOTV. This meant no need for enormous data and tech teams like Obama had, in 2008 and 2012. Besides, those dorks might tell them something they didn’t want to hear, like we need to spend more money on the field campaign. No way!
So Hillary's campaign paid for an artificial intelligence tool called “Ada,” which always told them to spend more money on TV ads (5). This meant ignoring furious warnings from Bill Clinton and SEIU, who tried to send buses of volunteers into Michigan, because they knew there was a problem there. "Turn that bus around, the Clinton team ordered SEIU" (6).
Both Obama campaigns tried to talk to every voter, multiple times, because that is how you find out where to deploy your resources. Which states are a lost cause and which ones are safe enough that you can move resources out of those states and put them where you need them to win close states like Michigan, Pennsylvania and Wisconsin. In 2016, it was obvious no one was doing anything with the data collected by door to door canvassers and phone bankers, because we were still talking to Trump supporters in the last few days of GOTV.
There are a number of other reasons Democrats will likely win. Trump is more than 8.5 points under water in his national net approval rating and people’s opinions about Trump are fixed. It's worse in Michigan and Wisconsin and just as bad in other battleground states. Wage stagnation and skyrocketing healthcare costs are having more of an impact on people than billionaires doing well in the stock market. Also, Republicans invested millions of dollars and decades of demonizing Hillary Clinton and she won't be on the ballot this time.
Granted, Republicans will cheat but they cheat in every election. There was massive and well organized cheating in 2004, via Karl Rove. In 2020, only 8 states will not have paper ballots: Texas, Louisiana, Tennessee, Mississippi, Kansas, Indiana, Kentucky, and New Jersey (7). It won't be close enough in those states to cheat the result.
I believe enough people know what happened in 2016, that if any campaign advisors try to pull that fake field campaign crap again, those people will be stopped. But the more people who know about this, the better chance we have of preventing it next year. Now you know. Please pass it on. For more details, take a look at the sources below.
(1) The Comey Letter Probably Cost Clinton The Election - FiveThirtyEight
https://fivethirtyeight.com/features/the-comey-letter-probably-cost-clinton-the-election/
(2) Did Russia Affect the 2016 Election? It’s Now Undeniable - Wired
https://www.wired.com/story/did-russia-affect-the-2016-election-its-now-undeniable/
(3) The Political Industrial Complex - Bill Moyers
https://billmoyers.com/story/political-industrial-complex-government-consultants/
(4) Hillary Clinton dwarfs Donald Trump in TV ad spending - CBS
https://www.cbsnews.com/news/2016-election-numbers-hillary-clinton-donald-trump-tv-advertisement-spending/
(5) How Trump beat Ada’s big data (Hillary's AI data tool) - Oxford University Press
https://blog.oup.com/2018/09/trump-beat-adas-big-data/
(6) How Clinton lost Michigan and blew the election - Politico
https://www.politico.com/story/2016/12/michigan-hillary-clinton-trump-232547
(7) Eight states to use paperless voting in 2020 despite security concerns - The Hill
https://thehill.com/policy/cybersecurity/457168-report-says-eight-states-to-use-paperless-voting-in-2020-despite